A number of patents have separately dealt with suits to protect the wearer from fires and harnesses to extract the wearer from a dangerous area or retard a fall. The prior art has not integrated a fire and explosion protection suit with a built-in extraction harness.
A number of patents teach safety harnesses. U.S. Pat. No. 2,979,153 to Hoagland et al. teaches the use of an internal harness which tightens onto the limbs of the wearer when used, which could cause further injury to the wearer. U.S. Pat. No. 3,973,643 to Hutchinson teaches a detachable waist harness in a fireman's turn-out coat. U.S. Pat. No. 4,273,216 to Weissmann teaches a harness mounted to the outside of a jacket. U.S. Pat. No. 4,682,671 to Hengstenberger et al. Teaches a harness loop that wraps under the arms and behind the head, and a jacket. U.S. Pat. No. 4,854,418 also to Hengstenberger et al. teaches the same harness and jacket with the addition of a crotch strap. Neither of the Hengstenberger et al. patents teach the use of a full body extraction harness integrated with the interior of a flash suit. It will also be appreciated that the harness loop arrangement of Hengstenberger et al. Is prone to causing neck injuries when in use. U.S. Pat. No. 5,960,480 to Neustater et al. teaches a harness inside a coverall. Like the harness of Hoagland, the harness fits loose most of the time, but cinches tight during a fall. U.S. Pat. No. 6,256,789 to Young et al. teaches a fall arresting harness integrated into a garment, in order to maximize the surface area acted on by the harness. The arrangement of the self-tightening harness is similar to those taught by Hoagland and Neustater et al.
Several patents assigned to E. I. Du Pont de Nemours and Company (“DuPont”) relate to fire resistant suits. None of these patents teach the use of an integral extraction harness. U.S. Pat. No. 5,048,124 to Lewis Jr. et al. teaches “Easy Access Protective Coveralls”, constructed of a shell to withstand high temperatures and laminated with a liquid impervious layer, and a multilayer liner. U.S. Pat. No. 5,050,241 to Flowers et al. Teaches a multilayer outer shell that has a vapor-permeable, liquid impermeable sheet sandwiched between a woven sheet and an insulating inner layer. U.S. Pat. No. 5,279,287 to Wiseman Sr. teaches a suit, similar to the suit disclosed in Lewis et al., made up of woven fabric with an aluminum layer adhered to it, and includes a detachable head and respirator covering. U.S. Pat. No. 6,490,733 teaches the use of a harness in a pant portion of a suit, but again this would not provides sufficient protection in a closed area where combustible gasses are present and could built up under a suit that was made of two separate garments. U.S. Pat. No. 6,487,725 teaches the storage of a lanyard in the harness, but does not provide for use of the lanyard without obstructing the work of the wearer.
Existing flash protection suits consist of a garment of one layer of flame protective cloth and a separate external fall harness layered on over the garment. The use of an external harness is inconvenient and can cause an explosion if the metal buckles and clips of the harness create a spark. These suits are used in situations where combustible gasses are present or build up, such as inside large pipelines or tanks, and where the risk of explosion is very high. In the case of an explosion, the person wearing the suit must be protected from possible burns due to the high temperatures. In addition, the force of the explosion will often render the person wearing the suit unconscious. The suit must also provide a way to retrieve the person wearing the suit without endangering the lives of those attempting the retrieval. Current suits with integrated harnesses place the harness on the exterior of the suit, which prevents a secure harness attachment to the wearer and allows the harness to shift and move. Moreover, an external harness decreases the effectiveness of the flame proof material by cinching and bunching the garment material against the wearer and thereby decreasing the thickness of the insulating material, squeezing out insulating air pockets, and allowing heat to penetrate the garment more quickly.
At this time there is no garment on the market that addresses the issues of multi-layered flash fire protection, retrievable built-in one-piece harness with lanyard, and respirator hose tie-down, in one protective garment eliminating the need for separate garments and harnesses to protect the worker.
At present, available off the shelve Fire Resistant (FR) Flash/Coverall garments merely meets the three-second test criteria to qualify as Fire Resistant material. These off the shelve single layer FR, natural or aramid, Personal Protective Equipment garments provide some thermal protection for a person engulfed in a gas vapor ignition for less than one to two seconds. Any exposure to the flash-fire over the three-seconds exposes the worker to significant thermal burns to the body and head. Within the field, it is highly desirable and sought-after to provide a flash suit capable of thermal protection for a person engulfed in a gas vapor ignition for at least eight seconds.
Needed is a multi-layer system that will provide added protection to the worker. A multi-layer flash suit must also provide unrestricted movement and comfort compared to single layer garments.